Improvement in the construction of ordnance



' D, and barrel A i Ihvirnn Spares. Partnr @rtree9 WILLIAM vWIIEELERIFIUBBELL, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IMTHE CONSTRUCTHON OF CRDNANCE.

Specification forming by declare the following to be a full, clear,

and exact description thereof, reference be ing had to the annexeddrawings, making part hereof, in which- Figure 1 is a section of theimproved gun, and Fig. 2 is a section of the gun with another form ofchamber and breech.

The nature of the invention consists in constructing large cannon ofsuch material, form, and proportions as to combine all the advantages ofwroughtiron or steel, without its dis`- advantages, with all theadvantages of bronze without its disadvantages. NVrought-iron or steelis superior to form the facing of the breech and bore, because theywithstand the effects of the lire better than other metal; but they canonly be constructed, with certainty and extreme strength, of a thicknessof about four inches, and when thicker, or of large body for an entirelarge gun, the iron or steel is not only but poorlyT welded, butgranulates rapidly by the vibrations of discharge, and is very liable toburst.. On the other hand, bronze or gun metal consisting of about nineparts of copper and one part of tin, or the base of which is copper,makes a strong gun; but it absorbs heat too rapidly for a large gun',and the intense action of fire on a bronze bore soon disintegrates ordestroys it by separating the tin and changing its size and form. It,Vhowever, has the advantage over iron or steel in malleability, non#liability to granulate or weaken by firing. Its vibrations are not asintense.

My invention retains all the advantage of the iron or steel and all theadvantage of Vthe bronze, by which I am enabled to make cannon of twelveand fifteen inches in the caliber, and capable 'of enduring from sixtyto one hundred pounds of powder for a charge, and of driving a shot withunparalled velocity and consequent destructive effect to crush ironcladvessels or forts. I- make a solid breech, n one piece of wrought-iron,

about three or four inches thick of metal at the breech, and taperingsmaller toward the muzzle.

slightly outside This breech and part of Letters Iatcnt No. @.LLELQLdated September 13, 1864.

barrel are welded in any of the well-known methods of forming andwelding gun-barrels. It should be made of bars and coils welded bypressure, and when turned uniform around it is suspended vertically in amold, in a heated state, and the bronze breech E and barrel B are castaround the breech and barrel in a solid body,so that there are no jointsfor the vibrations or strains to settle upon, but the entire strength ofboth metals is obtained. Around the bronze,when turned off, I shrink asingle sleeve of wrought-iron or steel,C,which clasps the bronze betweenits inner surface and the outer surface of the breech and barrel, behindthe trunnions, in one grip, without any joint for vibrations and strainsto settle upon. The bronze, being a malleable metal, takes up thevibrations and protects the outer band from their effects, while theouter band prevents the expansion of the bronze, and the inner iron orsteel protects the bronze 'from excessive fire and disintegration. Thusthese met als aid each other, andthe extreme strength of iron or steeland bronzeare obtained and applied ir. this gun without any of theirdisadvantages. The cascabel G shouldv 'or may be made large andcylindrical and curved off from the centers ff, to afford strength andbase of resistance to the action of the charges on the base of thebreech-chamber.

There are certain proportions or limits of these metals within whichthese maximum principles and results are most advantageouslyobtained-namely, for a fieldgun threeinches in the diameter ofthe bore,or four inches in the diameter ofthe bo-re, the wrought-iron or steel ofthe bore should be one inch thick at the muzzle and one and a-half inchthick at the breech as far forward as the trunnions, and taper-gradually from the trunnions to the muzzle.

For a fortification or a naval gun of six inches, or of eight inches indiameter in the bore, the thickness of the wrought-iron or steel of thebore at the muzzle should be two inches,

and the thickness at thebreech as far forward .as the trunnions shouldbe three inches and taper Vgradually toward the muzzle. For a ten-inchor a twelve-inch gun the thickness of the wrought-iron or steel of thebore a't the muzzle should be two and a half inches, and the'thicknessat the .breech be three and a half inches. For a lifteen-inch gun thethickness of the iron or steel of the bore at the muzzle 2 ld. R941should be two anda half inches, and the thickiron of the bore at themuzzle, and for large guns for iron-clads, to protect it from being tooeasily shattered by shot, the thickness of the bronze at the muzzle maybe about twice as thick as the thickness of the iron or steel of thebore at themuzzle. To give requisite strength at the breech to withstandvery heavy charges, the thickness of the bronze over and above or inaddition to the thickness of the iron or steel of the bore should besufiicient to make up a thickness equal to the measurement or diameterof the bore exclusive of the outer band of iron or steel, and the outerband. should be equal in thickness to the thickness of the inner iron'of the bore. Thus a fteeninch gun would have three and a half inches ofthickness of iron bore, eleven and a half inches of bronze, and threeand a half inches of an iron band, making eighteen and a half inches ofmetal thickness at the breech, to stand about eighty pounds of powderfor a charge with a shot of about four hundred and fifty pounds weight.In making a ritled gunsay of twelve inchesin the bore-to use abouteighty pounds of powder with about a tivehundred-p`ound elongated shot,the same, or eighteen inches, thickness of the met`als,should beretained, because it must always be observed that the strain on the gunis mainly due to tw'o causes-namely, the quantity of powder used and theweight or resistance of the projectile-and it is -increased byincreasing the elevation of the gun and increasing the quickness of thepowder.

As a general rule, taking the sizes of guns mentioned for sphericalshot, the ride-gun, to throw the same weight of shot of elongated form,with the same high charges and much greater range, should, although lessin diameter of the bore have the same thickness of metals at the breechas would be used for a smooth-bored gun using a spherical shot of thesaine weight. A general rule as to the length of the gun should be alength of bore equal to fifteen times its diameter, taking the and notreducl smooth-bore as the standard,

ing the length ot the riiie-gun, although its bore is reduced indiameter, to throw a projectile elongated and of the same weight as thespherical shot for the smooth-bored gun of similar length. rlhe properextreme limits ofthe thickness of the inner iron or steel of the boreare not less than one inch and not over six inches, the thickness beinggreatest, as stated, with larger sizes of guns. For light eldguns theentire thickness at the breech should be equal to the diameter of thebore. The outer band need not extend forward entirely to the trunnions,except where very heavy charges are intended to be used, and in case ofthis iron band extending as far forward as the middle of the trunnions,as shown in the drawings, the trunnions themselves may be ofiron weldedonto or forged with the band.

I am aware that suggestions have been made to construct guns ofcast-iron or bronze and iron or steel, and a flux, without definiteform, discrimination, and proportions, kind or construction of gun,(which I do not claim,) leaving the mattei' in an experimental andundetermined condition, not reduced to this positive form, proportion,use of metals, or discriminated construction and invention of mine,which special metals, form, proportions, and construction are necessaryto develop the maximum advantages, and my invention.

The trunnions may be cast of bronze with the gun, or separately attachedto it on Dahlgrens plan.

What I claim, therefore, as my invention isl. Casting the bronze withsolid breech and barrel in a solid body around the solid breech ofwrought-iron or steel, and the barrel united in one piece, in the formand proportions set forth, to combine the extreme strength and otheradvantages of both these metals, as described.

2. Shrinking or securing the one wroughtiron or steel band upon thebronze breech surrounding the solid wroughtiron or steel breech andbarrel, so as to clasp the bronze between the wrought-iron or steel ofthe band and the wrought-iron or steel of the breech and bore mostsolidly, in combination from the breech to the trunnions, substantiallyin the manner and for the purpose described. WVM. WHEELER HUBBELL.Vitnesses:

S. LAMB, J. F. BoUGH'rnR.

